The secret of Bono's great marriage -- his wife Ali

Ali Hewson does not live in the shadow of her famous husband Bono, and is uninterested in the trapping of celebrity. After 29 years of marriage, just celebrated, she knows her man and what she wants from the relationship.

A recent profile of Ali Hewson in the Irish Independent paints a portrait of a completely family-oriented woman who, despite her wealth and the global fame of her husband, is her own woman committed to helping others.

"She's very non-showbiz, very down to earth and genuine," says one source quoted in the Irish Independent piece. "She's sharp, realistic and very normal. With someone of her status you would think there would need to be a certain level of schmoozing, but there's no bulls*** about her.

As well as being a busy mother of four, Hewson has found the time to help Adi Roche with causes such as the Chernobyl Children’s Trust.

"Ali was a very quiet mother-of-two at the time I was trying to make the documentary. I tried to get hold of her for ages and eventually she agreed to meet me in Dublin,"said Roche

She remains fierecly private about her family

"It's a well-known rule with her that you don't ask about the family," according to one source quoted in the Independent piece. "She's perfectly friendly, but as soon as you start down that road the shutters go down and the interview is over."

Bono himself is on record as saying she is fiercely protective.

"My wife, Ali, is pretty private and she tries to keep all this away from them," he explained. "She's concerned about them I suppose. But I would love to talk about them."

On her passport she lists herself simply as "mother."

She seeks to ensure that her kids Jordan (22), Memphis Eve (20), Elijah (12) and John (10) live a normal life.

She has said. "Although they have so much more than myself and Bono did while growing up, we definitely don't spoil them."

U2 biographer Eamon Dunphy has stated that "the best thing about Bono is Ali ..."

"Bono's famously a nightmare after he comes off a tour," says one source close to the couple. "He's a child at heart and if Ali wasn't there, he'd be out every night. She can talk him down and keep him focused."

She is never concerned about losing Bono to another woman. She once said: "I don't feel threatened. You can live your life being scared of losing someone and, at the end of the day, if he is going to leave you, he'll leave you and that's it."